Incidence and risk factors of ankle fusion after pilon fracture: a retrospective review

Background: Pilon fractures are associated with a high incidence of complications, yet there continues to be uncertainty regarding variables associated with adverse outcomes after pilon open reduction and internal fixation (ORIF). This study sought to characterize the rate of arthrodesis and identify risk factors that increase the likelihood of ankle arthrodesis in patients with ORIF pilon fractures. Methods: After institutional review board approval, a retrospective review was conducted to identify patients who underwent ORIF of pilon fractures at an ACS Level I trauma center from 2005 to 2014. Medical records and radiographs were reviewed retrospectively for patient demographics, comorbidities, fracture characteristics, associated injuries, mechanism of injury, and functional activity. Logistic regression analyses were performed to identify risk factors associated with arthrodesis. Results: 282 pilon fractures (279 patients) met inclusion criteria. There were 182 men and 97 women with an average age of 43.8±15.2 yr. Overall, 15 pilon fractures (5.3%) in six male patients and nine female patients were treated with an ankle arthrodesis an average of 1.73±5.15 yr after their initial injury. Following multivariable logistic regression analysis, age greater than 40 yr, tobacco use, and nonunion were identified as independent predictors of arthrodesis. Conclusions: This study found a number of patient-related factors associated with an increased risk of arthrodesis after a pilon fracture was sustained. Multivariable logistical analysis identified age greater than 40 yr, tobacco use, and nonunion as independent predictors of arthrodesis following pilon fracture ORIF. Level of Evidence: Level III